TSH high and low: causes, symptoms and normal thyroid values

What causes a high TSH value? Often caused by hypothyroidism, it indicates a malfunction of the thyroid gland.

Have you collected the test results and the TSH value is high? Unfortunately, it means that the thyroid is not working properly. In medical terms, this is referred to as hypothyroidism and indicates that the gland is producing thyroid stimulating hormone in excess. Let's see what normal reference values ​​are and what happens when TSH is high or low.

High TSH: what does it mean?

The acronym TSH is used to indicate thyrotropin , or thyroid-stimulating hormone. It is a substance produced by cells of the anterior pituitary, which affects the functioning of the thyroid. When blood tests show a high TSH, it means your thyroid isn't working properly. Often, this deficiency manifests itself with the appearance of goiter, i.e. the enlargement of the thyroid gland, clearly visible in the neck.

In most cases, high thyrotropin is caused by hypothyroidism , which is a term for low thyroid hormone production. Sometimes, however, the value is unbalanced by a malfunction of the pituitary gland, which produces excess quantities. The other causes of low thyroid hormone, in addition to the ones just mentioned, are:

• Hashimoto's thyroiditis;
• antithyroid drugs;
• insufficient intake of thyroid hormones in the treatment of hypothyroidism;
• ectopic paraneoplastic production of thyroid-stimulating hormone-like substances.

In a healthy person, TSH has values ​​ranging from 0.4 to 4 µU/ml.

Low TSH: symptoms and causes

After looking at TSH and normal values, let's take a look at low TSH . When blood tests show a sharp drop in thyroid stimulating hormone at the same time as high T3 and T4 levels, it is likely caused by hyperthyroidism , or overactive thyroid gland . In addition to this cause, there are:

• Graves' disease;
• hot nodules, single or multiple;
• multinodular toxic goiter;
• pregnancy;
• excessive intake of thyroid hormones in the treatment of hypothyroidism.

The cure for thyroid hormone, whether it's high or low, depends on the patient's clinical condition and the type of thyroiditis that triggered the problem. It is therefore important to carry out all the necessary tests and have a discussion with an expert.